Morwenna Alldis from the RSPB South West asks the public this autumn/winter, to clean their nestboxes, or to install a new box, ready for winter roosting and next year’s breeding season.
Spring breeding season may seem an age away, but autumn/winter is actually the perfect time of year to focus on nestboxes. If you have an existing nestbox, a seasonal spruce-up is due and if you don’t have a nestbox - time to pop one up so that your garden birds can explore it before choosing where to feather their nest next year.
A nestbox in your garden, or attached to the side of your house, also provides essential shelter for garden birds during the cold snap. Winter nestbox roosts are often communal with several birds packing in for warmth. In fact, the record number of birds discovered in a nestbox is 61 wrens – now that’s cosy!
Pre Spring-Clean, Clean!
Old nest material can contain parasites and fleas which may linger and infest next year’s hatched juvenile birds. Ensure your nestbox is a pest free zone by removing old nests/nesting material (typically from September onwards, but always check the nest isn’t active first, as some species nest throughout this month too). Remember to wear gloves when handling nesting material and do not breathe in dust from the old nest or dried droppings.
You are also legally able to remove any unhatched eggs between September-January, but these must be disposed of.
Once your nestbox is empty, sterilise it using boiling water and let it fully dry out. Do not use insecticides of flea powder as these can be harmful to birds. To make your nestbox snuggly and inviting for winter visitors, pop a handful of clean hay or wood shavings in the bottom – but avoid straw as it can harbour mould.
Installing a new nestbox
Many natural nest sites have sadly been lost with the removal of hedges in favour of fences, modern building preferences that don’t feature eaves (house sparrows, starlings and swallows like to nest there) and the loss of trees. By putting up a nestbox you are giving nature a home and for me, there’s nothing more rewarding than watching your feathered friends start to explore their new pad and hopefully nest and raise their young in it – warm, fuzzy feelings guaranteed.
Nestboxes come in different shapes and sizes depending on the species – for example robins and wrens like an open fronted box, positioned low down and hidden in either a tree, shrub or bush. Whereas sparrows, tits and starlings like their closed, box homes fixed five meters up a wall or tree.
Remember also that different species need different sized entrance holes, enabling them to enter their home, but keeping predators out.
• 25 mm coal tits, marsh tits and blue tits
• 28 mm great tits and tree sparrows
• 32 mm nuthatches and house sparrows
• Starlings – their boxes should be 25-30% larger with an entrance measuring 45 mm
• The bottom of the entrance hole should be at least 125 mm from the floor – to prevent chicks falling out or cats getting a paw in.
Face your box north and east to avoid strong sunlight and the wettest winds. Also angle the box forwards slightly so that any rain will hit the roof and bounce off.
Also ensure that the birds have a clear flight path to the nestbox entrance without any trees or washing lines in the way.
And finally, when you flip the ‘Vacant’ sign on your swish, refurbished nestbox, remember to give the new tenants total privacy – no lifting the lid or putting an eye to the entrance whole (you wouldn’t want a giant peering through your window)! Instead, sit back and enjoy giving nature a home from a distance.
Last Updated: Tuesday 28 August 2018